Art of pressing wax-containing oil



July 9, l929- F. w. SULLIVAN, JR., ET AL, 1,720.30()

i ART OI; PRESSING WAX CONTAINNG' L 'Filed June lp 1925 l B l \D N nu)jwemm oil, etc., through the Patented July 9, 1929.

- AUNITED STATES PATENT OFFICE.

FREDERICK W. SULLIVAN, JR., WILLIAM J. MCGILL, AND HARRY L. WALKER, orWRITING, INDIANA, AssIeNoRs r.ro STANDARD orL COMPANY, or WRITING,INDIANA, A CORPORATION or INDIANA. n

AR'r or DRESSING WAX-coNTAINING` oIL.

Application filed June 1,

oil is supplied to the press through the pipe 7. A

A pipe 8, closed aty 'its inner end 9 passes through the press, beingsupported therein by the plates 10. Openings 11 are provided in plates10 around pipe 8 to permit free flow of press. A4 cylindrical chamber 12 secured to the head of the press surrounds the pipe 8; andto it isconnected the feed pipe 13 provided with two connections 14 and 15. y

Asmall chamber 16fcloses the end of pipe r 8 outside the press, and asmall pipev 17 extends through the chamber andthrough the greater partofthe length of the pipe 8. The small pipe 17 is open at its end. A drainpipe 18 is also connected to chamber 16.

In accordance with the present invention, the oil to be pressed, for.example, paraflin distillate is chilled to the desired low temperature.say .50O F. or lower in accordance with the nature of the oil and thecold test of the desired product, and is fed under pressure into thepress, its wax content being collected therein. For example, if a lowcold test is not desired in the oil product, the temperature duringpressing may be to 500 F. lf a low cold test oil is desired, the oil ispreferably put through the press two or more times, the first filtrationbeing at a temperature of 45 to 50 F. and the later filtrations attemperatures of 25C F. or lower.

. Tn ordinary operation, the oil to be pressed is forced through untilthe press is as nearly as possible filled with crude wax. This oper-v Aation ordinarily requires thirty hours or longer, the pressure requiredbeing considerably increased in the later stages of operation and thesize of the stream of oil product considerably diminishing after thefirst twelve or fourteen hours.

According to our method of operation, after 1925. Serial No. 34,030.

ten to fourteen hours of pressing, or when the wax content of the cakesin the press reaches aboutBO to 40%, the flow of oil through the feedpipe 7 is discontinued, andl water is forced through the press, forexample, through the pipes 15 and 13. Al-

though cold water may be employed, we pre-nv narily, from one half toone hour, and leaves the wax with an oil content of from to 60%. By theend of the operation, the temperature of the press has been raised,usually to 60 to 90o F. After the supply of water has been discontinued,if desired, the press may be filled .with wax by supplying to it a highwax containing oil; preferably, one containing 50% orhigherof oil. Thus,for example, Slack wax, or sweat oil from the paraffin sweaters, may beemployed, such products containing from 20 to 50% of wax and from 80 to50% of oil. This material is put into the press through the pipe 7, at atemperature at which at least part of the wax content is solid, suitablyat 60 to 800. The press is rapidly filled, the pressures required beingin general above 300 pounds,` and a final wax cake obtained containingfrornQOto 40% of oil (generally about 35%) and having a melting point ofabout 112 to 116o F. The press may then be cleaned, for example, by theuse of hot water supplied through the pipe 14 after a central channelhas been opened by the supply of steam through the pipe 17 to the pipe 8extending into the press. Prior to cleaning, however, water at atemperature below the melting point of the Wax may again be forcedthrough the press to remove oil 4from the wax, a reduction in oilcontent of 5 to 10% being thereby effected.

By operating in accordance with the pres-l ent invention, theeilticiency of the presses is very greatly increased, the time requiredfor filling the presses being substantially reduced and the rate of flow0f the oil, averaged over the entire pressing operation, being greatlyincreased.

We claim:

1. The method of filter pressing wax from hydrocarbon oils whichcomprises forcing Wax bearing oil through a ltering surface to build upa cake of Wax thereon, and forcing through said Wax dake Water at atemperature below the melting point of the Wax, thereby -temperature of75 to '110 F.

3. The method of operating a filter press for removing wax from waxbearing oilsl which comprises forcing chilled wax bearing oil throughthe press to build up wax cakes4 therein, discontinuing the flow of oiland forcing. through the wax in the press -water at a temperature belowthe melting point of the Wax until a substantial portion of the oilinthe wax in the press has been removed, and subsequently forcing a highWaxcontaining oil through the press at a temperature at which at least apart of the Wax content is solid.

4. The method of operating a filter press for the removal of Wax fromhydrocarbon oils comprising forcing a chilled Wax bearing oil through apress to deposit Wax therein, discontinuing the operation While the oil`content of the wax i's from 40 to 50%, forcing Watertherethrough, thetemperature of the .Water being about 100 F., to remove oil from the waxin the press, and 'subsequently forcing through the press an oilcontaining 20% or higher of Wax at a temperature at Which at least apart ofthe Wax content is solid.

FREDERICK WV. SULLIVAN, JR. WILLIAM J. 4MCGrILL HARRY L. WALKER.-

